Two-position valve actuators exist. One, known as the Jandy Valve Actuator (“JVA”) and sold by the assignee of this application, uses two cams to set the two positions. The cams may be adjusted manually following disassembly of the JVA, as may occur during installation of the actuator. No means of adjusting the cams dynamically during operation of the JVA exists, however, nor is there any way of stopping the JVA at a position other than the two positions created by the pre-set cams.
Multi-position valve actuators likewise exist. Generally, though, these actuators are complex and expensive, often employing closed-loop control not necessarily needed in pools and spas. These complex actuators additionally are difficult to integrate into existing automation systems of pools and spas.